Revert "Bug 950080 - add grunt jsdoc generator to gaia"

This reverts commit 508f3b37a2ea0953d2817464f285ec1d8b08dd2e.

Conflicts:
	Gruntfile.js
	package.json
Merge pull request #15741 from gaye/backout-bug-9500080

Revert "Bug 950080 - add grunt jsdoc generator to gaia"